1. Field of the Invention
The present invention relates to focusing methods, and more particularly, to a focusing method capable of capturing images of focus frames of all the characteristic points in the capturing area for making the captured images have clear images of all the characteristic points.
2. Description of the Prior Art
With advances of digital camera modules, almost all the electronic devices such as cell phones, tablets and personal digital assistants are now equipped with image capturing functions. When the electronic device with the digital camera module is required to capture a target, the electronic device starts a focusing procedure. In the conventional focusing procedure, the lens of the electronic device moves back and forth, and performs photo shooting on the target when the lens moves back and forth for acquiring a plurality of images. Then, the electronic device calculates the focus value of each of the plurality of images and determines a best focus distance according to the focus values. As a result, the electronic device can acquire the image containing a clear image of the target.
However, when the range that the electronic device is required to capture comprises multiple targets, the electronic device cannot precisely determine which one of the targets is the major target of the user, and cannot acquire the image that the user needs. Thus, how to capture images according to the multiple targets in the capturing area becomes a topic to be discussed.